package j06zhoukao;

import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class J1 {
    public static void main(String[] args) {
        Set<String> s = new HashSet<>();
        s.add(null);
        s.add("qq");
        System.out.println("s = " + s);


        String s1 = new String("qqq");
        System.out.println("s1 = " + s1);
        s1 = s1.intern();
        System.out.println("s1 = " + s1);

        System.out.println(s1=="qqq");//?


        Scanner sc = new Scanner(System.in);

        String s2 = getS();

        // [1,3,5,7,9,22,66,88,99]
    }

    static String getS(){
        String sx = new String("fff");
        return sx;
    }
}
